1. Field of the Invention
The present invention broadly relates to surgical instruments. More particularly, the invention relates to colposcopic biopsy instruments which have a punch end effector with means for collecting multiple biopsy samples.
2. State of the Art
The colposcopic biopsy procedure has become a widely practiced surgical procedure. The colposcope is an optical instrument, similar to an endoscope, which is used in conjunction with an endocervical speculum to examine the cervix. The procedure essentially involves inserting the speculum through the vagina and placing the distal end of the colposcope into the speculum. The speculum is manipulated until the cervix is at a right angle to the light of the colposcope. Upon examination, if abnormality of the cervical tissue is observed, one or several biopsy samples are obtained from one or several cervical locations with the use of a colposcopic biopsy forceps.
Colposcopic biopsy forceps generally include an actuating handle coupled by rods to an end effector assembly. The end effector assembly typically includes a pair of jaws one of which is rotatably coupled to the other, thereby allowing articulation of one of the end effectors relative to the other. The jaws are intended to achieve a cutting action through a punch and die configuration which severs the tissue from the joint by punching the tissue with a sharp edged jaw through a die. The die typically takes the form of a stationary jaw, while the punch takes the form of a movable jaw which rotates relative to the stationary jaw from an open position to a closed position when cutting. Some of these instruments take small, relatively superficial samples unless the practitioner stabilizes the cervix because they tend to slip away from the tissue as the jaws are closed. These instruments often crush rather than cut through the epithelium, often producing an unsatisfactory specimen. Other instruments have serrations on the die which aid in stabilizing the biopsy area. Still other instruments provide tooth-like projections on the punch which effectively stabilize the cervix, but tend to make a very deep cut resulting in excessive bleeding.
When collecting biopsy samples of the cervix, it is very important to record the location from which each sample was taken. The normal procedure is to take one sample, remove the forceps, and deposit the sample in an individual container. The forceps are then reintroduced through the speculum and another sample is taken. Typically, each sample is captured in and by the punch end effector so that it does not fall through the die. This arrangement makes it impossible to take multiple samples since the second sample would either fall through the die end effector or cause the first sample to become dislodged from the punch end effector.